230 - number of services

[cppoly]

Having a difficult time reading article 230 trying to determine what is considered one service or two services in the exhibits they provide.

For instance if you have one utility transformer, you could have two services coming from this transformer feeding two separate service equipment locations OR one service from this transformer feeding two separate service equipment locations. In both examples, you have only one utility transformer. What’s the difference in these scenarios?

 

[kwired]

One service can have multiple sets of conductors and multiple service disconnecting means (up to six disconnects is the maximum with some exceptions). The general rule also is those disconnecting means all need to be grouped at the same location.

Additional services are permitted for different characteristics such as different voltage, frequency, number of phases, even situations where the utility won't provide what is needed through a single service. You may run into that last one more often with single phase services over maybe 800 or 1000 amps and three phase services maybe over 2000 or even 4000 amps.

Additional permitted services don't have to be in same location as other services, you must provide signs that tell you locations of other service disconnecting means.

Many places will allow additional services if there is sufficient fire walls, rated partitions, etc. to effectively create a separate building, however the service for "building" generally can not supply loads in the other "building" in those installations.

 

[electrofelon]

Having a difficult time reading article 230 trying to determine what is considered one service or two services in the exhibits they provide.

For instance if you have one utility transformer, you could have two services coming from this transformer feeding two separate service equipment locations OR one service from this transformer feeding two separate service equipment locations. In both examples, you have only one utility transformer. What’s the difference in these scenarios?

It is a good question. The article 100 definition of "service" is quite general, so you really have to just look at the system and see how it fits in with 230.2 and 230.40. Note that 230.2 does specifically define a scenario with multiple sets coming off the transformer as being one service. I think most of the time, it will be clear whether it is multiple services or a single service with multiple sets of service entrance conductors. That said, I think there are some situations where both classifications are met. For example, consider 230.40 Exception #1, and 230.2(B)(1).

 

[Dennis Alwon]

Having a difficult time reading article 230 trying to determine what is considered one service or two services in the exhibits they provide.

For instance if you have one utility transformer, you could have two services coming from this transformer feeding two separate service equipment locations OR one service from this transformer feeding two separate service equipment locations. In both examples, you have only one utility transformer. What’s the difference in these scenarios?

I believe if you have 2 different locations, and code allows it, then you have 2 services. I don't really understand the second part- the way I read they are the same.

I always understood that if you had 2 runs from the power company then you had 2 services no matter if they are from one trany or two. Maybe I am incorrect but that has been my understanding

 

[electrofelon]

I believe if you have 2 different locations, and code allows it, then you have 2 services.

but I would disagree with that dennis because of 230.40 exceptions 1 and 3. As I said though, it does seem impossible to differentiate between one or two services sometimes for these situations.

I always understood that if you had 2 runs from the power company then you had 2 services no matter if they are from one trany or two. Maybe I am incorrect but that has been my understanding

But then you have 230.40 exception #2 and the text in the beginning of 230.2.

 

[LarryFine]

To me, the number of meters determine the number of services.

The POCO can run as many services from a transformer as they want.

 

[Dennis Alwon]

To me, the number of meters determine the number of services.

The POCO can run as many services from a transformer as they want.

I don't believe that is true Larry, in fact, I am almost certain that is not true. The number of meters does not count as more than one service.

 

[Dennis Alwon]

Service. The conductors and equipment for delivering electric
energy from the serving utility to the wiring system of the premises
served.

By this definition 2 runs from power company would be 2 services

 

[kwired]

I believe if you have 2 different locations, and code allows it, then you have 2 services. I don't really understand the second part- the way I read they are the same.

I always understood that if you had 2 runs from the power company then you had 2 services no matter if they are from one trany or two. Maybe I am incorrect but that has been my understanding

230.40 exception 2:


You can have one set of conductors or multiple sets of conductors supplying the permitted up to 6 disconnecting means or even any additional specifically permitted disconnecting means that are beyond 6.

something might have changed in wording in more recent years but I think intent of what can be done is still about same. I seem to recall it once saying something to the effect that six sets of conductors connected at their supply end but ending in six separate disconnects a the load end are still considered to be supplying one service. The copied text above is from 2020, but still allows exactly that, unless what I am thinking of is elsewhere in 230?

 

[electrofelon]

By this definition 2 runs from power company would be 2 services

230.2 specifically says two runs installed per 230.40 ex 2 is one service

 

[electrofelon]

As I said, I think 230.40 Ex 1 and 3 are where it can get murky

 

[kwired]

Here is what I was looking for earlier:


230.71Maximum Number of Disconnects.
(A) General.
The service disconnecting means for each service permitted by 230.2, or for each set of service-entrance conductors permitted by 230.40, Exception No. 1, 3, 4, or 5, shall consist of not more than six switches or sets of circuit breakers, or a combination of not more than six switches and sets of circuit breakers, mounted in a single enclosure, in a group of separate enclosures, or in or on a switchboard or in switchgear. There shall be not more than six sets of disconnects per service grouped in any one location.

For the purpose of this section, disconnecting means installed as part of listed equipment and used solely for the following shall not be considered a service disconnecting means:

Power monitoring equipment

Surge-protective device(s)

Control circuit of the ground-fault protection system

Power-operable service disconnecting means


That was copied from 2014, I think 2017 is nearly same, 2020 is changed though - main thing that is different though it is totally reworded is you can no longer have a main lug panel with two to six main breakers in it. Bold content above is not in there either, but has been in there for years before 2020.